2. What is Network ?
network is a collection of computers and devices
connected by communications channels that
facilitates communications among users and allows
users to share resources with other users
. Types of Networks Local Area Network
(LAN) Wide Area Network (WAN) Metropolitan Area
Network (MAN)
3. What is Network Security ?
Network security defined Network security is a broad
term that covers a multitude of technologies,
devices and processes. In its simplest term, it is a
set of rules and configurations designed to protect
the integrity, confidentiality and accessibility of
computer networks and data using both software and
hardware technologies.
4. Why we need to secure ?
Protect vital information while still allowing
access to those who need it Trade secrets,
medical records, etc.
Provide authentication and access control for
resources
Guarantee availability of resources
5. Hackers
Hacker someone who attempts to break into
computer systems to damage it, or for the purpose
of getting illegitimate access to resources
6. Cryptography
Cryptography
Cryptography is the science of concealing the
meaning of a message from unintended
recipients Only the intended recipient is able to
read and understand the message
7. Network viruses
Network viruses
A network virus is a self-contained program (or
set of programs) that can spread copies of itself
across networks, including the Internet.
In many cases, network viruses exploit
vulnerabilities in the operating system or other
installed programs. and they can use legitimate
network ports, such as port 80 (HTTP) and Local
Area Network (LAN) or even over the Internet to
spread. Some of the most famous network
viruses are Nimda and SQLSlammer .
Nimba , I love you ,
8. Wireless Network Security
The "open air" nature of wireless radio signals
posses challenges for securing wireless computer
networks.
Security features like
1. WEP
2. WPA
3. MAC
9. WEP (Wired Equivalent Privacy )
WEP (Wired Equivalent Privacy 128-bit)WEP is an OSI Data Link layer (Layer 2)
security
technology that can be turned "on" or "off.
WEP was designed to give wireless networks the
equivalent level of privacy protection .
10. Access Control
Host-to-Host Authentication. users authenticate
themselves once to a host computer. That computer
then authenticates itself to other computers.
Authentication Servers. the users authenticate
themselves to the authentication server. This
computer then authenticates the user to other
host computers
User-to-Host requires the user to log-in to each
host computer.
11. Access Control
Host-to-Host Authentication. users authenticate
themselves once to a host computer. That computer
then authenticates itself to other computers.
Authentication Servers. the users authenticate
themselves to the authentication server. This
computer then authenticates the user to other
host computers
User-to-Host requires the user to log-in to each
host computer.
